<p>Development of floodplains in the western rural areas of NSW is managed through Part 8 of the Water Act 1912. Part 8 was gazetted in 1984 and makes provisions concerning 'flood control works' that affect, or are likely to affect, flooding or floodplain functions. Part 8 was amended in 1999 to allow for more strategic control of flood control works through the preparation of rural Floodplain Management Plans (FMPs) and a more streamlined and resource efficient approval process. The amendments also required that rural FMPs be developed in accordance with the provisions and policies of the operative NSW Manual (currently, Floodplain Development Manual, NSW Government, 2005).

<p>The manual supports the primary objective of the New South Wales Government's Flood Prone Land Policy to reduce the impact of flooding and flood liability on individual owners and occupiers of flood prone property, and to reduce private and public losses resulting from floods, utilising ecologically positive methods wherever possible. The formulation and implementation of FMPs is the cornerstone of the policy and the process for their preparation is described in the manual.

<p>Administrative orders published in April 2007, inter alia, divided the responsibilities under Part 8 of the Water Act 1912 between the Department of Environment and Climate Change (preparing rural FMPs) and the Department of Water and Energy (implementing the plans through licensing and compliance functions).

<p>On 1 July 2009, following a Reorganisation of Government Agencies, the licensing and compliance functions regarding Part 8 were transferred to the newly established Office of Water within the renamed Department of Environment, Climate Change and Water (DECCW). Please note that any reference in this document to the Department of Environment and Climate Change, and Department of Water and Energy, is to be construed as a reference to DECCW.

<p>The development of a rural FMP progresses through three (3) key stages:

Data Collection & Flood Study (FS) - in general, includes data collection for hydrology, hydraulic and environmental aspects; defines the nature and extent of flooding, including development of a computer-based hydraulic model of flood behaviour;

Floodplain Risk Management Study (FRMS)- in general evaluates management options based on hydraulic modelling, analysis of the floodplain environment and social and economic considerations, to address existing and future floodplain risk management issues; and

Floodplain Management Plan (FMP) - presents the recommended management measures for the floodplain, as determined in the Floodplain Risk Management Study, and includes an implementation program with priorities.

<p>This current project, overseen by the Darling River Floodplain (Bogan River confluence to Louth) Floodplain Management Committee (the Committee) and prepared for DECCW, includes only the first of the above three elements of the Floodplain Management Plan process, and is structured as follows:

<p>Stage 1: Data Compendium and Digital Terrain Model

<p>All information and knowledge of the flood regime in the study area are included in a Compendium of Data (COD), as a permanent record, and for later use in Stage 2 of the FS.

<p>A Digital Terrain Model was prepared for hydraulic modelling use in Stage 2 of the FS and the results presented on an appropriate Geographic Information System (GIS).

<p>Stage 2: Calibrated Hydraulic Model and Final Flood Study Report

<p>A calibrated computer based hydraulic model was developed to quantify the distribution of floodwaters during historical flood events and for later use in designing a floodway network (as part of the FRMS) in order to evaluate management options.

<p>The Compendium of Data was completed in July 2008. This Report covers Stage 2: Calibrated Hydraulic Model and Final Flood Study Report.

<p>The Commonwealth Government's Natural Disaster Mitigation Program (NDMP) and the New South Wales State Government through the NSW State Emergency Management Committee (SEMC) have jointly provided funding for the project.